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arXiv · 0802.3707

Rings and Jets around PSR J2021+3651: the `Dragonfly Nebula'

Adam Van Etten·Roger W. Romani·C. -Y. Ng
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Abstract

We describe recent Chandra ACIS observations of the Vela-like pulsar PSR J2021+3651 and its pulsar wind nebula (PWN). This `Dragonfly Nebula' displays an axisymmetric morphology, with bright inner jets, a double-ridged inner nebula, and a ~30" polar jet. The PWN is embedded in faint diffuse emission: a bow shock-like structure with standoff ~1' brackets the pulsar to the east and emission trails off westward for 3-4'. Thermal (kT=0.16 +/-0.02 keV) and power law emission are detected from the pulsar. The nebular X-rays show spectral steepening from Gamma=1.5 in the equatorial torus to Gamma=1.9 in the outer nebula, suggesting synchrotron burn-off. A fit to the `Dragonfly' structure suggests a large (86 +/-1 degree) inclination with a double equatorial torus. Vela is currently the only other PWN showing such double structure. The >12 kpc distance implied by the pulsar dispersion measure is not supported by the X-ray data; spectral, scale and efficiency arguments suggest a more modest 3-4 kpc.

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Adam Van Etten, Roger W. Romani, C. -Y. Ng. 2008-02-25. Rings and Jets around PSR J2021+3651: the `Dragonfly Nebula'. https://doi.org/10.1086/587865

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